Who is the goddess Pele and how is she related to the origin of the Hawaiian Islands?

Pele is the Hawaiian goddess of fire. She traveled by canoe from near Tahiti to Hawaii. She migrated down the islands, trying to start her fires, but her sister Namaka chased her, trying to kill her. Pele's body was destroyed in a battle with Namaka near Hana, Maui.

Her spirit now lives in the Halemaumau crater on Kilauea. Her body is the lava and steam that comes from the volcano. She can also change form, appearing as a white dog, old woman, or beautiful young woman.

I suggest you read Pele by Herb Kane or Hawaiian Legends of Volcanoes by Westervelt, both are available from the Hawaii Natural History Association.

One of the more interesting stories is how Pele was being forced to go from island to island as she was chased by various other gods (most of whom were her relatives). This journey of hers went from the island of Kaua'i to the island of Hawai'i where she presently lives. This progression happens to very well correspond to our modern scientific notion of the age of the volcanoes. Additionally, there are a number of places on the older islands where she is reported to have rested along her way. All of these are young volcanic features on these otherwise old eroded volcanic islands. The Hawaiians are very good at recognizing volcanic features, and did a good job of working these into their stories.